Gravitational separator



J. v.sLADE.

GRAVITATIONAL SEPARATOR. 'APPLICATION FILED JAULYSI i920- 1,405,022'l Patented Jan. 31, 1922.

3 SHEETS-SHEET l- I. v. SLADE.

GRAVITATIONAL SEPARATOR.

APPLICATION FILED IIuLYsI, 1920.

1:495022. t Patented Jan. 31, 1922.

3 SHEETS-SHEET 2.

1. V; SLADE. GRAVITA'TIONAL SEPARATOR. APPLICATION FILED JULYSI, 1920.

1,405,022, Patented Jan.31,1922

3 SHEETS-SHEET 3.

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Jaivcns VINCENT smania, or NEW rena, N. iv., AssreNon ro rire noaa corfirANY, A

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Specickation of Letters Patent. lPQU-@d Jan, 319 19220 Application led July 31, 1920. Serial No. 400,412.

To all whom #may concern: l

Be it known that I, JAMES VINCENT SLADE, .a citizen of the United States, residing at lNew York, in the county of NewYork, State of New York, have invented certain new and useful lmprovements in Gravitational Separators; and l do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable lothers skilled in the art to which it appertains to make `and use the same.

This invention relates to gravitational separators or thickeners and has for its object the provision of certain improvements in'such apparatus. e

Gravitational separators or thickeners are of wide .application in many industries where it is desirable or necessary to separate slimes,

sludge, or solid matter in general, from a liquid containing the same. lin its usual form2 the gravitationalvseparator consists of a sedimentationl or decantation compartment adapted to contain the liquid under treatment and provided with means for appropriately decanting substantially clear liquor from near the top' of the compartmentand with means for working settled solid matter towards a solids discharge outlet in the bottom of the compartment. ln practice, it 'is customary to continuously supply the raw or untreated liquid to the sedimentation and decantation compartment and to continuously decant the substantially clear liquor from near the top of the compartment and to continuously discharge a thickened product containing a relatively high 'proportion of solid matter from the bottom of the compartment. Frequently, a plurality of superposed sedimentation and decantation compartments are embodied in a single structure, in which case it' is the usual practice to provide independent .agencies for permitting the flow of substantially cleai liquor from near the top of each compartment.'

The settled solid matter may be independently discharged. from the bottom of eachcompartment, or the superposed compartments may have a common solids-discharge path and outlet, in which event-the combined solid matter' from .all of the compartments may be discharged through an appropriate outlet in the bottom of the lowermost compartment.

The rate of decantation, that is to say, the

rate of the flow of substantially clear liquor from near the top Iof the sedimentation and decantation compartment of a gravitational separator, is determined by the hydrostatic head. provided by the difference in level of the liquid in the compartment and of the discharge end of the outlet for-the decanted the form of a vertical stand-pipe communieating with the sedimentation and decantation compartment nearethe top thereof and arranged to have its discharge end raised or lowered by manually putting on or taking off an appropriate number of superposed rings which are held in place by appropriate guides projecting from the natural upper or dischar e end of the standpipe. Where hot or corrosive liquids are under treatment, this simple method of regulating the flow of decanted'liquor from the sedimentation and decantation compartments becomes diiicult and awkward, and the improvements of the present invention will be found of especial advantage in the treatment of liquids of this character in gravitational separators, more -particularly of the tray or superposed compartment type. v i

In accordance with'the present invention the liquid outlet or outlets of the gravitational separator` are provided with mechanically operable .adjusting means for adjusting .the eifective level or height of the discharge end of each liquid outlet and for thereby regulating the. {iowv of decanted liquor from cach compartment. rlhus, the

liquid 'outletjnay include a vertical standipe whose upper or natural discharge end is lower than the normal level of the liquid in the separator, 'and a mechanically operable adjustin member may be ,associated withthe upper end of the standpipe for adjusting the height of the effective discharge end of the liquid outlet. ll`he liquid outlets of the superposed compartments of a tray separator are capable of independent adjustment, and where desired means may be provided for simultaneously .and similarly adjusting the effective discharge ends of all ofthe liquid outlets of the tray separator.

"llhe novel features of the invention which l believe to be patentable are definitely set forth in the appended claims. 'lhese features, Atogether with the construction and mode of operation of apparatus embodying the same, will be understood from the following description, taken in conjunction with the accompanying drawings, in which Fig. 1 is a sectional eleva-tion of a gravitational separator of the tray type embodying the present invention; K

Figs. 2, B and d are detail views illustrating the mechanically operable adjusting means for the liquid outlets of the supe-rf* posed compartments o-f the separator shown in Fig. 1;

Figs. 5 and 6 are detail views of a modified mechanical construction of the adjusting means; and

Figs. 7 and 8 illustrate ay construction by v which theeffective discharge height. of all sedimentation'and decantation compartments 12. lThe trays 11 are secured at their outer periphery to the cylindrical side wall of the tank 10, and at their centers have registering openings from which depend boots 13. Where the separator is employed for the treatment of hot liquids, the outer and exposed surfaces of the tank 10 may be covered with a llayer of heat insulating mate-rial 14.

The trays 11 are preferably inclined and slope from their outer peripheries towards the openings at the centers thereof. The depending boots 13 are in alinement and form in effect a solids-discharge path, common to the three settling compartments 12.

A revolving sludge-collecting -mechanism is operatively mounted within the` tank 10. This mechanism comprises a vertically disposed shaft 15 rotatably carried in approj pria-te over-'head bearings secured to .the super-structure 16:v The shaft,15 is slowly rotated in any appropriate manner, as, for example, by a worm gear 17, driven from a motor 18 through appropriate instrumentalities. The shaft 15 extends downwardly through the boots 18. Three pairs of radially disposed arms 19 are appropriately secured tothe shaft 15 and are arranged to rcincense ed is fed. @ne or more skimming arms 22 may, if desired, be secured to the shaft 15 near the top of the drum 21 and serve to direct any material `floating on top of the liquid in the drum 21 into an appropriate discharge launder 23. ln the construction illustrated in Fig. 1, the skimming arms are pivoted or hinged to horizontal rods radiating from the shaft 15, by which construction the skimming arms readily turn on their pivots or hinges in passing over the inner end of the launder 23. Y

rll`he bottom of the. tank 10 is provided with a discharge cone`2a for the discharge of the combined solid matter from all of the superposed settling compartments 12. rllhe discharge of solid matter through the cone 24C is preferably eiected by a diaphragm pump 25 which is connected to the cone 24C through; a solids-discharge pipe 26. rllhe pump 25 is of the uniform or constant. displacement type, that is to say, at each stroke it removes a. fixed predetermined volume ofsludge or thickened product from the separator. The ultimate density of this thickened product will generally be such that the ratio of solids to liquidl in the product will be of the approximate order of one to one. By appropriate adjustment, the pump isoperated in such a manner that the volume of thickened product of the ultimate density withdrawnl from the separatorA in a giveninterval of time contains substantially the same average amount o-f solids as is contained in the V01-, ume of mixeod. solids and liquor sup-plied to the separator in the same time interval. When-thus properly adjusted, the constant displacement. pump acts in the nature of a regulator, thereby insuring the proper functioning of the gravitational Aseparator as 'a sedimentation and decantation apparatus.

ica v Substantially clear liquor is decanted or withdrawn from the upper part of each of the three settling compartments 12 of the decanting connections are moreover arranged near the outer circumference of the settling compartments. The decanting connections are equally spaced about the outer circumferential portion of the settling compartments, and while I have shown in the accompanying drawings only three decanting connections, more or less may, if desired, be employed. 1

The decanting pipes 27, 28 and 29 are independently connected to standpipes 27', 28' and 29'. The standpipes 27", 28' and 29' extend into a sump 33 and terminate at a level below the normal liquid level inthe separator. The sump 33 has, a depending discharge pipe 34 communicating with thel bottom thereof.

The upper or outlet end of each of the `stand'pipes 27', 28' and 29' is equipped with a `metal packingring 35 which may conveniently be screw-threaded onto the standpipe, as illustrated in Fig. 4 of the drawings. Hollow cylindrical adjusting tubes 36 are fitted over the metal packing ringsI 35 and have an inside diameter approximately the same as the outside diameter of the packing rings, thereby forming an effective seal against the flow of liquid out of the lower end of the adjusting tubes.

rl`he upper ends of the tubes 36'are open except for a small fraction of the circumference occupied by flanges 36'. These anges are' in fact a continuation of the cylindrical wall of the tube. A U-shaped bracket 37 is riveted, or otherwise appropriately secured, to the anges 36'. A screw-threaded rd 38 is secured to each of the brackets 37 and op-v eratively engages a stationary nut 39 mounted on a bracket 40. The brackets 4Q may be riveted to, or otherwise appropriately securedto, the walls of the sump 33. Each of vthe rods 38 is provided with an operating wheel or handle 41. The rod 38 may be so secured to the bracket 37 as to permit free rotation of the rod without necessarily rotating or turning the tube 36.

`ln the modification illustrated in Figs. 5

and 6 of the drawings, a vertically disposed rack 42 is secured to the bracket 37. An appropriately supported pinion 43 operatively engages the rack' 42 and is adapted to be' turned by a hand wheel 44. The rack 42 may conveniently be supported between the pinion 43 and a spring member 45, the latter serving to maintain the rack -in its adjusted position.

In the modicationillustrated in Fig-s. 7 and 8 a vertically disposed rodl46 is secured tothe bracket 37 of each ofthe adjustingv tubes or sleeves 36. The upper end of eac 'of the-rods 46 is operatively secured to one end of a lever 47 ivotally mounted on a fulcrum shaft. 48. he other or outer ends of the levers 47 are connected to a common crank shaft 49 by independent tiefrods v50.

'ach of the tieQrods 50 includesl a turnshaft may be turned and appropriately adjusted'fby a hand wheel 54. -It will be observed that the movement of the crank shaft 47 simultaneously and similarly adjusts each of the tubes 36. u (l The apparatus illustrated in the accompa. nying drawings is particularly adapted for the separation of solid matter from sugar juices. This type of apparatus has been illustrated merely for the purpose 7of explaining the principles of the invention, and I wish it to be understood that apparatus embodying the invention is adapted for use in any industry whee the separation of solid matter from a liquid containing the same is to be accomplished. The operation of the 'apparatus illustrated in the accompanying drawings, as especially applied to the sugar he.

industry, is substantially as follows. sugar juice from which solid matter is to be separated is fed into the cylindrical loading Well 21 at such a rate as to maintain the liquor level in the well slightly lower than the lower edge of the skimmers 22. Any foam'fwhch may form on the surface of the liquid in the well 21 is brushed into the launder 23 by the skimmers 22 and may be disposed of by combining it with the sludge discharged by the pump 25. The solids in suspension in the liquid in thevarious cornpartments 12 tend to settle out on the tra'y bottom, leaving clear liquor in the upper portions of the compartments. Due to the height of the liquid in the loading well 21, the clear liquor inthe upper portion of each of the compartments 12 will vtend to` flow through the decanting pipes 27., 28, 29, through the stand-pipes 27', 28' `and 29', respectively, and so overflow the upper edge of the adjusting tubes 36. `Theiiow of clear lllO liquorfrom any one of the three compart v Under such circumstances, it is advisable to` reduce the rate of flow through this compartment. This result maysbe accomplished by turningthe appropriate handI wheel 41 so as to raise the cooperating tube 36 and thereby decrease the effective hydrostatic head of the intermediate compartment 12,

whereupon the rate ,ofl flow through this compartment is reduced. It will be evident that by raising the adjusting tube 36 to a still further height, the flow ot clear liquor canting ments.

through the cone 2a and are withdrawn 'fromthe tank through the pipe 26 by the pump 25, and may, it desired, be mixed with the oating solid matter discharged through the launder 23,

Prior to the present invention, means usually employed for controlling the -flow of liquor from the superposed settling com.- partments of a tray separator or thickener comprise a multiplicity or rings, about` onef quarter inch in thickness and of the same internal and external diameters as the destandpipes. 'llhese rings were loosely placed on the top of' the standpipe and were held in place by three vertical guide rods'xsecured to the outer periphery of the standpipe. ln order to change the flow with 'such an arrangement, it is necessary to have a great number of these rings on hand and to place them on one another and to remove them by hand.` lin many instances, this arrangement has no particular disadvantages, but when treating ,corrosive liquids( or hot`liqiids, as for example, in the manufacture of caustic soda, alumina, phosphoric acid, sugar, etc., it is diiiicult and sometimes dangerous for the operator to manipulate the rings. Thus, where the liquids under treatment-are corrosive or hot, it 1s necessary tohandle the rings by means of pliers or tongues, and this is an awkward, trouble'some and time-consuming procedure.

By the improvements of the present invention, it is only necessary to turn the hand wheels 41 (or the hand wheels le or the turn buckle 5l) in order tol secure the desired regulation of the How of clear liquor from the superposed settling compart- Moreover, by the arrangement of the invention, a far more accurate and fine adjustment is possible than can be attained by the use of superposed rings. Moreover, by similarly and simultaneously regulating the efective height of thev liquid outletsof all ofthe 'settling compartments appropriate adjustment may readily be made for any fluctuations in the level of the liquid in the tank 10. Such an adjustment is especially valuable where the supply or feed is not entirely constant or uniform, as `for eX- ample, in the sugar industry.

l cla-im:

l. lin a gravitational separator having a Q plurality of 'superpqsed sedimentation and 70 decantation compartments, a liquid outlet communicating with each or said compartments near the top thereof for permitting the flow ot liquid from each compartment,

each of said liquid outlets including a verti- 75 cal standpipe whose natural discharge end is lower than the edective operating liquid level in said separator, and a mechanically Aoperable adjusting member associated with each oit said standpipes and adapted by its so adjustment to regulate the effective levell of the discharge' end of the standpipe.

2. ln a gravitational separator having a yplurality ot' superposed sedimentation and decantation compartments, a liquid outlet at communicating with each of said compartments near the top thereof tor permitting the flow off liquid trom each compartment, mechanically operable adjusting means associated with each oit said liquid outlets tor e@ regulating said flow ot liquid trom each of' said compartments, and means whereby alloifv said ladjusting means may be simultaneously and similarly adjusted tor simultaneously regulating to the same extent. the

ow ot liquid trom each ot said compartments.

3. ln a gravitational separatorhaving a plurality of superposed sedimentation and decantation compartments, a liquid outlet 10o communicating with each of said compartments near the top thereof for permitting the How of liquid from. each compartment, each 'of said outlets including a vertical standpipe whose natural discharge end is lower than the effective operating liquid level in said separator, a vertically movable tube operatively associated with each of said i standpipes and 'adapted by its adjustment to regulate the effective level of thedischarge end of the standpipe, and means for independently radjusting each of said tubes.

4. lin a gravitational separator having a.

vplurality of superposed sedimentation4 and decantation compartments, a li uid outlet ycommunicating with each of sai compart ments near the top thereof for permitting the How'of li uid from each compartment, each of said liquid outlets including a vertical standp'ipe whose natural discharge end 120 is lower than the effective operating li uid level in said separator, a tube adapte to `fit snugly over the discharge end of each of said stand ipes, a packing between said tube and sai liquid llowing through said standpipe to flow over the lip of the tube, and'means for independently raising and lowering each of said tubes so 'asI to raise or lower the coun. terhead of the liquid How in said separator. l isp standpipe adapted lto cause l 5. ln a gravitational separator having a plurality of superposed sedimentation and decantation compartments, a vertical 'standpipe associated with each of said compartments, a tube adjustably mounted on the discharge end of each of said standpipes, and means for raising and lowering each of 'said tubes individually so as to vary the counterhead of the flow of liquid in each compartment. 4

6. vIn a gravitational separator having a plurality of superposed sedimentation and decantation compartments, a liquid outlet communicating with each of said compartments near the top thereof for permitting lthe flow of liquid from each compartment,

-level in said separator,4 a vertically movable tube operatively associated with each of said standpipes and adapted by its adjustment to regulate theeffective level of the discharge end of the standpipe, means for individually adjusting each of said tubes and means whereby all of said tubes may be simultaneously and similarly. adjusted.

In testimony whereof I affix my signature.

JAMES VINCENT sLADEf 

